Question Author
Churchill is the answer to another one.
Of the list from Wikipedia, these are the ones I haven't used
Edward Smith-Stanley, 14th Earl of Derby
William Grenville, 1st Baron Grenville
Spencer Compton, 1st Earl of Wilmington
Lord John Russell 1st Earl Russell
Frederick John Robinson, 1st Viscount Goderich
William Petty, 2nd Earl of Shelburne
Henry John Temple, 3rd Viscount Palmerston
Archibald Primrose, 5th Earl of Rosebery
George Grenville MP for Buckingham
David Lloyd George MP for Caernarvon Boroughs
Bonar Law
Clement Attlee
David Cameron
George Canning
Gordon Brown
Henry Addington
Henry Pelham
James Callaghan
John Major
Neville Chamberlain
Sir Anthony Eden
Sir Henry Campbell-Bannerman
Spencer Perceval
Stanley Baldwin
Theresa May
Tony Blair